Although the scope of the problem of aggression and physical violence between family members has begun to emerge from the research of the last few years, to date there has not been a single investigation using a representative sample of the population. Consequently, even the descriptive question of the frequency with which family members use physical force on each other is unknown, but probably high. A national sample survey of couples with at least one child at home will therefore be carried out to provide information on the following questions: (1) How frequently is physical violence used between family members? Data will be gathered on violence in parent-child relations, sibling-sibling relations and wife-husband relations, but the study emphasized husband- wife violence. Husband wife violence has been particularly neglected, yet we feel it is crucial for understanding other manifestations of intrafamily violence, including child abuse. (2) What is the subjective meaning of acts of physical violence between family members and to what extent are different types of violent acts normatively approved or disapproved? Previous research indicates the existence of a dual and conflicting value system with respect to intrafamily violence which needs to be clarified. (3) To what extent are certain sociological theories of the causes of violence--resource theory, conflict theory, and structural theory--applicable to the case of intrafamily violence? In addition to detailed analysis of these three theories, exploratory analyses will be done on a variety of other possible correlates of family violence such as alcohol use, selected attitude and personality characteristics, and the degree of social isolation versus integration of the family with a social network of relatives and friends.